Reaction of Li with O2 in the presence of He or Ar

The reaction of Li with O2 in the presence of He or Ar was studied at a temperature near 150 0C for inert gas pressures between 29 and 1500 Torr. In both cases, the rate of loss of free Li atoms was linear with O2 partial pressure between approximately 0.003 and 1.3 Torr, but had a more complex dependence on inert gas pressure. In He, the reaction probably proceeded by means of the energy transfer mechanism where the dominant intermediate was LiO2*. The results in Ar are consistent with a reaction occurring through both the energy transfer mechanism in which LiO2* plays an important role and the bound intermediate complex mechanism where LiAr is the primary intermediate